Right-angle 40-pin header for board-edge routing
Gold on the mating surface (8.00 µin thick) gives the contacts a decent corrosion barrier and moderate cycle life for a signal connector.
Pitch, positions, and plating against close siblings
The 40-position count is the main differentiator from the 12-position 5176837-5 and 10-position 5176837-4 — same pitch, same right-angle form, same 1 A rating. The gold mating finish on this part is 8.00 µin thick, which is thinner than the 30.0 µin on those two siblings. For a signal-only header in a controlled environment, the 8.00 µin gold is adequate; if the application sees frequent unmating or a corrosive atmosphere, the thicker plating on the lower-position variants is worth the swap.